New member from West Sacramento

[Yukon 6]

In the diagram wiring diagram there's a red wire coming off the fuse that powers all those selenites the fuse is good do I was going to check it down to transmission and see if there's not a problem between the fuse in the transmission I know all the solenoids didn't just go out at once so if I get power down there what's the transmission then I will take it to your transmission shop if I don't get power I would assume is something between the fuse in the transmission

 

[wjburken]

In the diagram wiring diagram there's a red wire coming off the fuse that powers all those selenites the fuse is good do I was going to check it down to transmission and see if there's not a problem between the fuse in the transmission I know all the solenoids didn't just go out at once so if I get power down there what's the transmission then I will take it to your transmission shop if I don't get power I would assume is something between the fuse in the transmission

William, my friend, you need to slow down and proof read your posts. It will make it a lot easier to help if we know what you’re talking about.

Folks here want to help, but helping diagnose stuff over the internet is tough enough when communication is clear. When SIRI adds her 2-1/2 cents worth and autocorrects and guesses at what you are saying, it is downright impossible sometimes.

 

[Yukon 6]

William, my friend, you need to slow down and proof read your posts. It will make it a lot easier to help if we know what you’re talking about.

Folks here want to help, but helping diagnose stuff over the internet is tough enough when communication is clear. When SIRI adds her 2-1/2 cents worth and autocorrects and guesses at what you are saying, it is downright impossible sometimes.

 

[Yukon 6]

I got you i need to quit voice typing yeah those post were not very comprehensive. Let me start over in words you can understand my front differential locked up while I was going 25 or 30 mph the truck skidded to a complete stop the front differential had chunks of metal in it so i got a rebuilt differential and installed it when i got all done the check engine light was on and it was in limp mode. Prior to this it had gone into limp mode a couple of times over a 4 month period and once in a while when i started it the red neutral light would come on which is for towing and its still doing that now when I turn it off and start it again it will show normal most of the time the front of the front output shaft seal on the transfer case has a small leak but the case is full also the traction control light is on. My vehicle is a 2004 gmc yukon with awd there is a switch for 4 lo but there is no 4 hi just so you understand this is awd also it wont shift into 4 lo i apologize for my previous post and thank you very much for your kindness and patience my vehicle has a 6inch lift but it has always done fine for the5 years ive had it it did go into limp mode a year after igot it they put a remanufactured pcm in it and flashed it i did have the battery disconnected for about a week is there any possibiity the tcm might need to be reflashed? And i did have a ignition problem awhile back for abou 4 months where it didnt want to turn over unless I tried several times sometimes it would take ten minutes to start but it seemed to fix it self it hasnt done it for a long time ionly say that becuse last time before the computer being replaced it was doing the same thing anyway the codes im getting now are P 0740 0753,0758,0785 and 2167 one is the tcc enable solenoid circut and the others are 1and 2 and there are two 2and 3 shift solenoid circuit whic would lead me possibly to believe there is a problem in the wiring in that circuit or bad tcm module again thank you for your response

 

[wjburken]

I got you i need to quit voice typing yeah those post were not very comprehensive. Let me start over in words you can understand my front differential locked up while I was going 25 or 30 mph the truck skidded to a complete stop the front differential had chunks of metal in it so i got a rebuilt differential and installed it when i got all done the check engine light was on and it was in limp mode. Prior to this it had gone into limp mode a couple of times over a 4 month period and once in a while when i started it the red neutral light would come on which is for towing and its still doing that now when I turn it off and start it again it will show normal most of the time the front of the front output shaft seal on the transfer case has a small leak but the case is full also the traction control light is on. My vehicle is a 2004 gmc yukon with awd there is a switch for 4 lo but there is no 4 hi just so you understand this is awd also it wont shift into 4 lo i apologize for my previous post and thank you very much for your kindness and patience my vehicle has a 6inch lift but it has always done fine for the5 years ive had it it did go into limp mode a year after igot it they put a remanufactured pcm in it and flashed it i did have the battery disconnected for about a week is there any possibiity the tcm might need to be reflashed? And i did have a ignition problem awhile back for abou 4 months where it didnt want to turn over unless I tried several times sometimes it would take ten minutes to start but it seemed to fix it self it hasnt done it for a long time ionly say that becuse last time before the computer being replaced it was doing the same thing anyway the codes im getting now are P 0740 0753,0758,0785 and 2167 one is the tcc enable solenoid circut and the others are 1and 2 and there are two 2and 3 shift solenoid circuit whic would lead me possibly to believe there is a problem in the wiring in that circuit or bad tcm module again thank you for your response

Thanks. That’s a lot clearer.

It has been a while since I dealt with that vintage of vehicle so I’m not going to claim to be an expert, but for me, a lot of stuff is pointing to transmission/transfer case control issues.

I believe someone that was familiar with a Tech 2 would be able to go in and see what is going on with your shift solenoids and your transfer case controls. @Doubeleive and @swathdiver are the first two guys that pop into my head that could give some direction in the Tech 2 arena. I am sure there are others but I can’t think of them at the moment. If your Transfer Case is shifting into neutral or worse, into 4-L, you can do serious damage to your drive train like shell out a front differential or something in your transmission.

Now that you have more clearly stated your dilemma, there are others here that are more familiar with your vintage that can offer more complete advice than I can.

 

[Doubeleive]

ya I don't know with things being changed out and flashed I would go back to whoever did the initial work and the flash and see what they can figure out, there were some Denali's that had a selectable awd but I think those were previous to 04, could be wrong

 

[swathdiver]

I'm not as familiar with those older ones but the transmission does not like transfer case oil in it and the transfer case does like transmission fluid in it. If the seal between the two is leaking, that is where your problems originated. Don't ignore those telltale signs that something is not right cause its gonna cost you.

My eyes are failing and those big volumes of words are pretty blurry to me these days. Start by checking the level and condition of the fluids in both the TC and Transmission. If there is no contamination or level issues, then proceed to troubleshoot the codes. Who do you know with a Tech-2? They're about $350 and can save you a ton of money. Subscribe to AllDataDIY for the shop manual too.

 

[Yukon 6]

Thank you guys I really appreciate it this forum and the people are really great thanks again

 

[Yukon 6]

I'm not as familiar with those older ones but the transmission does not like transfer case oil in it and the transfer case does like transmission fluid in it. If the seal between the two is leaking, that is where your problems originated. Don't ignore those telltale signs that something is not right cause its gonna cost you.

My eyes are failing and those big volumes of words are pretty blurry to me these days. Start by checking the level and condition of the fluids in both the TC and Transmission. If there is no contamination or level issues, then proceed to troubleshoot the codes. Who do you know with a Tech-2? They're about $350 and can save you a ton of money. Subscribe to AllDataDIY for the shop manual too.

The transfer case on this vehicle takes the same fluid as the transmission nonetheless i would think like you say a leak between the two could not be good

 

[Yukon 6]

Thanks. That’s a lot clearer.

It has been a while since I dealt with that vintage of vehicle so I’m not going to claim to be an expert, but for me, a lot of stuff is pointing to transmission/transfer case control issues.

I believe someone that was familiar with a Tech 2 would be able to go in and see what is going on with your shift solenoids and your transfer case controls. @Doubeleive and @swathdiver are the first two guys that pop into my head that could give some direction in the Tech 2 arena. I am sure there are others but I can’t think of them at the moment. If your Transfer Case is shifting into neutral or worse, into 4-L, you can do serious damage to your drive train like shell out a front differential or something in your transmission.

Now that you have more clearly stated your dilemma, there are others here that are more familiar with your vintage that can offer more complete advice than I can.

I am just curious when you say transmission or transfer case control would that mean the tcm possibly?